In the end, the Ohio Republican's efforts, along with the help of Sens. Bob Corker of Tennessee and John McCain of Arizona, helped Cordray get a whopping 17 Republicans to support moving forward with his nomination for a full appointment atop the CFPB.

In a conference call with Ohio reporters, Portman — who has been working for months to defuse the GOP-led filibuster threat on Cordray — said the vote to limit debate was "a bigger vote than I expected, frankly, because we were able to get certain assurances from Rich Cordray regarding some accountability measures we talked about."

Portman said Cordray has agreed to testify before the Senate Appropriations Committee, even though the committee does not have jurisdiction over the CFPB because it is funded directly from the Federal Reserve. Portman also said Cordray pledged to implement cost-benefit analysis of CFPB regulations.

A CFPB spokeswoman would not confirm that Cordray had agreed to use specific cost-benefit tool, but she said the agency head has offered to provide staff briefings to the Appropriations panel.

"Director Cordray and the staff of the CFPB are always happy to brief members of Congress about the work of the agency," the spokeswoman said. "He told several members that the CFPB is willing to provide an informal briefing on our budget, as we have done many times in the past."

Corker said the effort to get GOP votes for Cordray started with about three senators before getting the much larger number. He said several other Republicans might have voted in favor of the motion to end the filibuster if it had been necessary.

Sen. Lindsey Graham said that while he supports more changes to the CFPB, the Dodd-Frank banking law that created the agency is the law of the land.

"The law is the law, and you know, if you don't like the law, repeal it," the South Carolina Republican said. "You know, that's my view. I just think using an appointment to change a law is not the right use of an appointment."

That statement was a turnabout for Graham, who joined dozens of other GOP senators in vowing previously to block any nominee to the CFPB until the law was changed to their satisfaction.